An electric propulsion system, comprising a propeller and a motor arranged to rotate the propeller, the motor comprising an axial flux motor comprising a rotor disc and a stator disc mounted in face-to-face relationship with an air gap defined therebetween, the rotor disc driven to rotate relative to the stator disc to cause magnetic flux in the air gap to cause rotation of the propeller, characterised in that the propeller is directly attached to the rotor disc to rotate with the rotor disc.

An electric propulsion system, comprising a propeller and a motor arranged to rotate the propeller, the motor comprising an axial flux motor comprising a rotor disc and a stator disc mounted in face-to-face relationship with an air gap defined therebetween, the rotor disc driven to rotate relative to the stator disc to cause magnetic flux in the air gap to cause rotation of the propeller, characterised in that the propeller is directly attached to the rotor disc to rotate with the rotor disc.

Provided are a stack-type stator having coil patterns patterned on a multi-layer substrate, and a motor and a blower for an air purification system using the stator. A stack-type stator includes: a multi-layer substrate having first through holes; coil patterns formed on the respective substrates of the multi-layer substrate and spirally patterned to surround the first through holes and to form a plurality of turns; a stator yoke disposed at a lower portion of the multi-layer substrate and having second through holes at positions corresponding to the first through holes; and divided cores each having one side protruding above the coil patterns formed on the uppermost layer of the multi-layer substrate and the other side being coupled to one of the second through holes through one of the first through holes.

The described technology relates to a stator of a planar type motor and a planar type motor using the same, which are easy to manufacture and are capable of reducing core losses, thereby maximizing motor performance. First cores that are difficult to form by stacking electrical steel plates are formed of soft magnetic powders, and second cores that are formed by stacking electrical steel plates having the same size are arranged in a region where a vortex is concentrated, thereby allowing easy manufacture and being capable of maximizing the performance of the planar type motor.

The described technology relates to a stator of a planar type motor and a planar type motor using the same, which are easy to manufacture and are capable of reducing core losses, thereby maximizing motor performance. First cores that are difficult to form by stacking electrical steel plates are formed of soft magnetic powders, and second cores that are formed by stacking electrical steel plates having the same size are arranged in a region where a vortex is concentrated, thereby allowing easy manufacture and being capable of maximizing the performance of the planar type motor.

A stator assembly for an electric motor includes a drive plate, a first magnetic core and a second magnetic core. A first core slot is formed in the first magnetic core and a second slot is formed in the second magnetic core. The first and second magnetic cores each include two elongated members joined at one end by a base member which are defined by the respective core slots. The two elongated members extend from the base member substantially parallel to each other toward the drive plate. A stator coil is wound through the first core slot and the second core slot. An electrical current flowing in the stator coil generates a magnetic field about the stator coil that is absorbed by the first magnetic core and the second magnetic core to generate a magnetic flux in each of the magnetic cores that magnetically attracts the drive plate.

A stator assembly for an electric motor includes a drive plate, a first magnetic core and a second magnetic core. A first core slot is formed in the first magnetic core and a second slot is formed in the second magnetic core. The first and second magnetic cores each include two elongated members joined at one end by a base member which are defined by the respective core slots. The two elongated members extend from the base member substantially parallel to each other toward the drive plate. A stator coil is wound through the first core slot and the second core slot. An electrical current flowing in the stator coil generates a magnetic field about the stator coil that is absorbed by the first magnetic core and the second magnetic core to generate a magnetic flux in each of the magnetic cores that magnetically attracts the drive plate.

A reluctance motor is presented. The reluctance motor comprises a rotor and a stator, where the stator comprises two end stators and at least one stator mid plate (4, 23) with stator mid plate teeth (13, 23A, 23B), and the rotor comprises at least two rotor plates (3, 22) with rotor plate teeth (14, 22A, 22B). The at least one stator mid plate (4, 23) and the at least two rotor plates (3, 22) are arranged between the two end stators (1, 21).

A method and apparatus for operating an electric motor is presented. A transmit magnetic field is received at a group of receive coils having a group of axes oriented substantially parallel to magnetic field lines from a transmit coil and having a group of resonant frequencies. A resonant frequency in the group of resonant frequencies is different from other receive coils in the group of receive coils. A receive magnetic field is generated at a receive coil in the group of receive coils having the resonant frequency when the transmit magnetic field has a selected frequency matching the resonant frequency. The receive magnetic field attracts a rotor in the electric motor.

A method and apparatus for operating an electric motor is presented. A transmit magnetic field is received at a group of receive coils having a group of axes oriented substantially parallel to magnetic field lines from a transmit coil and having a group of resonant frequencies. A resonant frequency in the group of resonant frequencies is different from other receive coils in the group of receive coils. A receive magnetic field is generated at a receive coil in the group of receive coils having the resonant frequency when the transmit magnetic field has a selected frequency matching the resonant frequency. The receive magnetic field attracts a rotor in the electric motor.